Railway-traffic-controlling apparatus.



A. V.'T. DAY.

RAILWAY TRAFFIC CONTROLLING APPARATUS.

APPLICATION FILED EUNE 9,1903.

1,163,069. Patentvd 1m. 7, 1915.

Kigali 9 Mtwesmy [rm/a tar M i 5 m Luz 1 ALBERT v. T. DAY, or newROCHELLE, NEW YORK, MENTS, To HALL SWITCH & SIGNAL COMPANY,

TION 0F MAINE.

RAILWAY-TEAFFIC-CONTROLLING APPARATUS.

Specification of Letters Patent.

ASSIGNOR, BY MESNE ASSIGN- OF NEW YORK, N. Y., A CORPORA- PatenteApplication filed June 9, 1908. Serial No. 437,502.

To all whom it may concern Be it known that I, ALBERT V. DAY, a citizenof the United States, res1ding at New Rochelle, in the county ofWestchester and State of New York, have invented a certain new anduseful Improvement in Railway-Trailic-Controlling Apparatus, of- Whichthe following is a specification, reference being had therein to theaccompanying drawings, forming part thereof.

My invention relates broadly to electric systems for controlling railwaytrains by means of signals, automatic stop mechanism, or other deviceslo'cated upon the train itself, and the object of the invention is toproduce a system of this kind which shall be simple in construction andreliable in operation.

One novel feature of the invention is the means by which the electriccommunication is maintained between the fixed portion of the apparatusand the moving portion carried by the car or train. In the: illustratedform of my invention this means is embodied in the track rails, and asto this embodiment of the means for maintaining communication betweenthe fixed portions of the apparatus and the moving portions carried bythe car or train, my invention con sists broadlyin electricallyresponsive signaling or traflic-controlling apparatus carried on thetrain and connected with the train wheels in such a manner that theelectric current which governs this train apparatus may be conveyed toand from the train by means of the track rails only, thus dispensingwith an extra contact conductor, the track rails being included in thecircuit which supplies controlling current to the train apparatus insuch a manner that, in tracing this c1rcu1t, the current willfl'ow tothe train by Wayof one or more track ralls and! will then flow through aconductor comprised in the train apparatus and thence through one ormore of the track rails away from the train. That is to say, in lieu ofemploying one or more track rails as one conductive lead to the trainapparatus and employing an extra contact conductor as the other lead, umy invention broadly contemplates the utilization of the track rails asboth leads. broadest aspect is not limited to the employment of thetrack rails as conductors for track rails,

However, my invention in its conveying controlling current to the traintaining communication with the train apparatus, the utilization of thedifference in potential between different points on a fixed conductorthrough'which a current of electricity is flowing, the train beingprovided with two contact members engaging the conductor at two points,and with apparatus connected across these contact members and responsiveto the flow of current due to the difference in potential between thetwo points. However, I preferably utilize the or one of them, as thefixed conductor, and for the contact members I preferably ut lizetwo carwheels when one rail is employed and two pairs of car wheels when tworails are employed, the said wheels or, pairs of wheels, beingpreferably one in advance of the other, and still more preferablybeingthe foremost and re'armost on thecar or train. When an alternatingor periodic current is transmitted along the rails extending between thetwo wheels or two pairs of wheels, the difference in potential betweenthe'points engaged by these wheels, due to the impedance of the rails,causes a flow of current through a conductor, preferably of lowimpedance, connecting the axles of the wheels; and this current may beutilized directly or inductively to actuate a signal on the train, suchas a sensitive audible signal for instance, or may be inductively ordirectly employed to actuate a sensitive relay carried by the train andcontrolling a cab signal, automatic stop mechanism, or othertraffic-controlling means. When I thus employ the track rails and carwheels in a circuit to control a sig nal or other traffic-controllingdevice carried on a car, my invention will preferably be embodied in anarrangement whereby this use of the track rails will not interfere withusing them as conductors in track circuits which control block signals;and my invenapparatus, and whether or not the track ralls are thusemployed, 'my invention broadly. comprehends, as a means formaintrolling system embodying the invention, as applied to thewest-bound track of a doubletrack railroad. The east-bound track andthe'apparatus connected therewith are ,not'

vention the track rails} are continuously conductive and are utilized asthe fixed conductor above referred to, while the wheels of the train areutilized as contact members.

A train or car is illustrated in block A-BI The forward pair of wheels 2and the rear wheels 3 may be the forward and rear wheels of a singlecar, or the forward and rear wheels of'a train of cars. These forwardand rear wheels are connected by a conductor 4 preferably of lowimpedance, and whenever a current is transmitted through the rails 1extending between the two pairs I of wheels, a portion of the current isdiverted through the conductor 4, owing to the difierence of potentialbetween the wheels 2 and 3 due to the impedance of the rails betweentheir points of contact. In the illustrated system alternating currentis transmitted through the rails, and theconductor l is usedinductively, as the primary of a transformer, of which-the secondary 5is connected with a relay 6 and a telephone receiver 37 both carried bythe train.,

A condenser 7 is interposed in the relay circuit, and its capacity isadjusted relative to the inductance of the relay so as to establishresonance of thecircuit for that particular frequency of current whichcomes from the signaling generator 14. In other-words,'the condenser isadjusted relative to the inductance of the relay so as to tune thecircuit to the frequency of the signal current. This permits the use ofthe rails as conductors for alternating traction current. in an electricrailway, provided the frequency of the traction current is substantiallydifferent from that of the signal current, since the resonance of therelay circuit makes it selectively responsive to the current of thatparticular frequency with which it is in resonance. Also, so long as thetraction current is substantially different from the signaling current,the sound produced by the signaling current in the telephone receiverwill be readily distinguishable from the sound produced by the tractioncurrent.

The train relay 6 controls a contact finger 8 incircuit with a cabsignal 9 and a slgnal battery 10. So long as the relay is energized thesignal circuit is closed and the signal 9 is maintained at safetyposition by current from battery 10; but when the signal current flowinfrom the rails through the conductor 4 is interrupted and the relay isdeenergized, the contact finger opens the signal circuit and the signalmoves, in obedience to its normal bias, to danger position. Also, whilethe signal current fiows through the conductor 4:, it will produce inthe telephone receiver the characteristic sound which constitutes aclear signal, but when the current is discontinued the sound isdiscontinued in consequence, to give a danger signal.

The-train apparatus above described may be used, as illustrated, inconnection with a block signal system of the type in which the signalsare controlled by track relays connected with inductive track coils, thetrack rails being normally energized by an alternating current. In thedrawing the'continuously-conductive track rails 1 are 'connected at theends of the blocks by heavy cross-bonds 11 of negligible impedance, andat or near the middle of each block the rails are connected with thesecondary terminals of a transformer 12. The transformer is energized byconnection with transmission wires 13 fed by an alternatingcurrentgenerator 14. Each block constitutes a divided track circuit, andthe alternating current passes from one terminal of the transformeralong the rail connected therewith to both ends of the block, thencethrough the cross-- bonds 11 to the other rail, and back through thatrail'to the other terminal of the transformer. This current normallyenergizes inductive coils 15 andlfi located within and close to therails at the ends of the block, and these coils energize relays 17 and18 controlling the signal circuits.

The signal relays are of the polarized alternating-current type, havingfield magnets constantly energized, through feed wires 19 and 20,403transformers 21 connected with the transmission wires 13. Each relay hasa pivoted armature 22 provided with a coil connected with one of thetrack coils. Each armature has a contact finger 26 or 28 by which theline-circuitof the signal is controlled, and so long as both the fieldmagnet and the armature coil are energized by alternating currents ofthe same frequencizfiy;l and proper phase relation, the contact ger ismaintained in contact with the cooperating fixed contact; but when thearmature coil is denergized, or energized by current of a phase which isopposite to that required to close the relay contacts, then the contactfinger falls and opens the line-circuit of the signal.

The transformers 12 of adjacent blocks are similarly connected to trackrails; that is to say, while one transformer is delivering positivecurrent to the rail 1 uppermost in the diagram, the transformers of theadjacent blocks are also delivering positive cur-.

rent to that rail. As a result of this mode of connection, the trackcoil at the end of one block cannot be effectually energized by currentfrom the transformer of the adjacent block, in the event of anaccidental break in the cross-bond which normally limits the current ofeach transformer to its own particular block. For example, suppose thebond 11 is broken, and current flows from the transformer 12 of block BCrearward through the track rails and through the front wheels and axleof a train just in rear of the track coil 15 Since this current flowsaround the track coil 15 in a direction opposite to normal flow ofcurrent from the transformer 12 of block AB, the current induced in thetrack coil 15 by current from the block BC can only ener-.

gize the relay armature 22 in a direction opposite to the normaldirection, thereby tending only to keep the relay contacts morepositively open.

The signals 23 have a normal bias to danger position, but are heldnormally clear by means of any usual or suitable electri-"cally-controlled device arranged inthe linecircuit of the signal. Theline-circuit by which signal 23 is controlled passes from signal battery24 through line wire 25 to contact finger 26 of relay 17", through thecontact finger and its fixed contact to line wire 27, back to station B,through fixed contact and contact fingers 28 of relay 18 thence throughwire 29, to signal 23 and thence back to the battery.

So long as the track coils 15 and 16 are energized at both ends of theblock by the inductive action of the track circuit, the

foregoing line-circuit of the signal 23 remains closed and this signalat the entrance end of the block stands clear. As soon, however, as atrain enters any portionof the block the wheels, by bridging the railsbetween transformer 12 and one of the track coils, short-circuit one orboth of the track coils, and the signal circuit is consequently openedby one of the relays. The signal then goes to danger and remains sountil the train leaves the block.

The current from transformer 12, since it flows in opposite directionsinthe two rails at every point in the block, has no effect on the trainsignal apparatus, but the latter is controlled by another currentflowing in the same direction through the two rails as parallelconductors. This train-signal current is controlled by the block signalapparatus, being automatically interrupted in a block by the sameoperation which places in danger position the signal at the entrance tothe next block in advance.

To control the train-signal current two controllers, 30 and 31, areconnected mechanically with each semaphore 23, or with the mechanismwhich actuates the semaphores, the contact fingers being therebyactuated in conjunction with the semaphore. These circuit controllersare connected in circuit with the transformers 21 and the track railsand the line wires 83 so that when they are in proper position currentfrom the transformer 21 passes through the track rails from one stationto another. In order to economize the electric energy, the contactfingers 30 and 31 are arranged to keep these circuits normally open, butupon the entrance of a train into a block the circuit in that block isclosed, provided the block -AB for the purpose of clearing visual trainsignal 9 and actuating the audible train signal 37 This circuit is asfollows: from feed wire 19 through wire '32 to circuit controller 30(which engages its fixed contact so long as the block BC next ahead isclear), thence through line wire 33 to circuit controller 31 and itsfixed contact, and thence through wire 34; to the rail uppermost in thediagram at the point where the cross-bond 11 is located. From thiscross-bond the current flows through the two rails equally to cross-bond11 and thence to the wire 35 connected with the track rail lowermost inthe diagram at the point where the cross-bond 11 is located,,and throu11 wire 35 to feed wire 20 So long as t e track signal 23 ahead of thetrain remains clear and the signal behind is set at danger,

the block occupied by the train thus energized to maintain the trainsignals clear.

If the block ahead of the train be occupied, the circuit. abovedescribed'is held open by the action of the signal at the entrance tothat block. If, for example, block B-C be occupied, signal 23 havingrisen to danger position, holds circuit controller 30 in open-circuitposition andthus the closing of circuit controller 31 does not completethe circuit through block 'A'B and the train signals are not cleared.The train signals thus act as distantsignals, for, immediately upon theentrance of the train into a block, the position or sound of the visualor audible trainsignal indicates the position of the transformersbodiment of my invention derived from the same source as the blocksignal current, it has the same frequency as the block signal current inthe track rails, and, therefore, in order that the former may not haveany ac tion on the relays governed by the inductlve track coils, it isnecessary to divide the train-signal current equally between the tworails, so that its inductive action on the opposite sides of the trackcoils may be balanced and neutralized. For this purpose the wires 34:and 35 are connected at opposite ends of the cross-bonds 11 and thesecross-bonds are of such negligible impedance that the track portion ofthe circuit for the train-signal current includes both rails equally, sothatthe currents in the two rails are equalized.

The transformers 21 are all connected with the track rails'so as todeliver thereto currents having the same phaseand instantaneous polarityas the currents from the 12. That is to say, while'the transformers 12are delivering positive current to the rail uppermost in the diagram,'this rail is also receiving positive current from each transformer 21Which'happens to be in closed connection with the rails by way of thewires 19 and 32, contacts 30, line wire 33, contacts 31, and Wire 34.This mode of connection insures that, in the event of a brokencross-bond or rail, or both, the relay controlled by the track coil atone end of a block shall .not be effectually energized by thetrain-signal current flowing through the adjacent block. For example,suppose that the cross-bond 11 is broken.

Current from the Wire 34 will then fiow rearward along the right rail(uppermost in the diagram) to the front wheels and axle of anapproaching train and thence to the left rail and thence forward alongthe left rail, thus passing around the coil 15-'. If the right rail isconcurrently broken in advance of the cross-bond 11 all the current fromthe wire 34: will thus flow around the coil 15 But in either case, thecurrent thus flowing around the coil 15 will energize the relay armature22 in a direction opposite to normal flow of current around the trackcoil from the transformer 12 of the block A-B.' Also, underotherconditions, as, for example, when a break. occurs in one rail, thetrain-circuit current may be trans mitted through one rail only so as toaffect the inductive track coils of the same block through which thetrain current is intended to flow; but under such conditions theoperation of the system is still such as to give a danger indication atthe entrance to that block. Suppose, for example, that the train hasreached a point in the block B --G be tween the transformer 12 and thesignal 23 and suppose that one rail is broken between that signal andthe train. The-track coil 16 should now be deenergized and itscorresponding relay 18 should open the linecircuit through signal 23 andthat signal should remain in danger position. With the signal 23 in thisdanger position, the circuit controller 31 will close the circuitvthrough block BC for the train-signal current from transformer 21 andthis train-signal current will flow through the unbroken rail. Thiscurrent, being unbalanced by corresponding current in the broken rail,will tend to energize the track coil, and the track coil will delivercurrent to the relay 18 which will either tend .to close the contactscontrolled by the relay, or will tend to open such contacts, accordingto the phase" or instantaneous direction of current inthe armature ofthe relay relative to the current in its field magnet. This relativephase or instantaneous direction depends upon which track rail is brokenand which one is energizing the track coil. But we may suppose that therail uppermost in the diagram is broken, and current for operatingthe'train-carried signals in the block B-C flows Wholly through thelowermost rail, in which event it will energize the track coil 16 in theproper direction to close its contacts controlled by the relay 18 Thusthe line-circuit of the signal 23 is completed, even with the train inthe rear half of the block, but as the signal starts to move to clearposition and before it can'move an appreciable degree, the contacts 31are opened, thus opening the circuit for the train-signal current, sothat the relay 18 is again denergized. The signal thereby has aninappreciable chattering or oscillating action, while remaining at orsubstantially at danger position,-and a clear indication cannot be givenin spite of the unbalanced flow of train-signal current in the unbrokenrail.

It will. be apparent that the method of operating the train'signal orother controlling device carried-by the train may be used in connectionwith any traffic-controlling system arranged to suitably control thecurrent in the rails, and it is obvious that, although the track railsand the train wheels are in, illustration, but in practice-a moresensitive relay, of any usual or suitable form, may be employed torender the apparatus traffic-controlling means and a car or train havinga plurality of contact members, a

fixed conductor engaged by said contact .members, means dependent on thecondition of the stationary trafiic controlling means for electricallyenergizing the conductor, and car or train controlling means carried bythe car or train and responsive to the dif ference in potential of thecontact members.

2. An electric traflic-controlling system comprising, in'combinationwith a car or train having a plurality of contact members, a fixedconductor engaged by said contact members, means for energizing theconductor with a periodic current, and car or train controlling meanscarried by the car or train and responsive to the diflerence inpotential of the contact members.

3. An electric tralflic-con'trolling system comprising, in combinationwith a car or train having two contact members, a fixed conductorengaged by said contact members, means for energizing the conductor witha periodic current, a transformer carried by the car or trainand havinga primary conductor connected with said conta'ct members,

and electric car or train controlling means con nected with thesecondary winding of the transformer.

4. An electric traflic-controlling system comprising, in combinationwith track rails and a car or train provided with two contact membersengaging one of the rails, stationary traffic-controlling means, meansdependent upon the stationary traific-controlling means forelectricallyenergizing said rail, and electric car or train controllingmeans carried by the car or train and responsive to the difference inpotential of the contact members.

5. An electric traffic-controlling system comprising track rails, meansfor transmitting a current through the two rails in arallel, a car ortrain having a plurality-of contact members engaging the rails at pointsof different potential, and electric car or train controlling meansresponsive to the difference in potential of the contact members.

6. An electric trafiic-controlling system comprising, in combinationwith track rails and a car or train, means for transmitting a currentthrough the two rails in parallel, and electric car or train controllingmeans carried by the car or train and responsive to the difference inpotential between the train wheels engaging said rails.

n electric traffic-controlling system comprising, in combination with acar or train and the track rails, means for transmitting a currentthrough the two rails in parallel, electrically controllabletraflic-controlling apparatus carried-by the car or train and arrangedto receive controlling electrical energy from a difi'erence of potentialbetween two wheels of the car or train, and a traffic-controlling trackcircuit in control of the traflic-controlling apparatus and includingthe track rails leading to the said two wheels as the sole conductorsemployed to lead traffic-controlling current to the car or train,whereby an extra contact conductor is rendered unnecessary.

8. An electric signaling system comprising, in combination with a car ortrain and the track rails, means for transmitting a periodic currentthrough the two rails in parallel, electrically responsive signalingapparatus carried by the car or train and arranged to receivecontrolling electrical energy from a difference of potential between twowheels of the car or train, and a signal-controlling track circuit incontrol of the signaling apparatus and including the track rails leadingto the said two wheels as the sole conductors employed to leadsignalcontrolling current to the car or train, whereby an extra contactconductor is rendered unnecessary.

9. An electric trafiic-controlling' system comprising, in combinationwith track rails and a car or train, means for transmitting a periodiccurrent through the two rails in parallel, and electric train or car,controlling means carried by the car or train and connected with twowheels thereof, one in advance of the other.

10. An electric traffic-controlling system comprising, in combinationwith track rails and a car or train, means for transmitting a periodiccurrent through the two rails in parallel, and electric car or traincontrolling means carried by the car or train and comprising atransformer of which the'primary conductor is connected withztwo wheelsof the train one in advance of the other, and electrically-responsiveapparatus connected with the secondary winding of the transformer. 1

11. An electric traffic-controlling system comprising, in combinationwith stationary traific-controlling means and track-rails and a car ortrain having a plurality of contact members engaging one of the rails,means dependent on the stationary traffic-controlling means fortransmitting a periodic current through said rail, and electric car ortrain controlling apparatuscarried by the car or train and responsive tothe difference in potential of the contact members, saidapcomprising, incombination with a car or train having a lurality of contact members,

stationary tra c-controlling means, car or train controlling meansearned by the car or train, andmeans for connecting said stationarytraflic-controlling means and car or train controlling meanscomprising-a fixed conductor and means rorproducing a flow of currenttherein, said conductor being engaged by the contact members at'pointsof different potential.

13. An electric traffic-controlling system comprising, in combinationwith track rails and a car or train having two contact members engagingone of the rails, stationary signals, means controlled COIIJOlIltlY withsaid signals for producing a current in said rail, and car or traincontrolling means carried by the train and responsive to the differencein potential of the contact members.

14. An electric traffic-controlling system comprising, in combinationwith track rails, a stationary signal, means operating to produce aperiodic current through the two rails in parallel when the signal isclear in advance of a car or train, and car or train controlling meanscarried by the car or train and connected with two wheels thereof, onein advance of the other, the train-controlling means being responsive todifference in potential of the said wheels.

15. An electric trafiic-controlling system comprising, in combinationwith track rails and cross-bonds constitutlng track circuits,

stationary traffic-controlling means operated by said track circuits, acar or train having cmitact members engaging the rails at points ofdifierent potential, electric car car 01' train controllin "car or trainand responsive to the difierence in potential of said contact members,and

means or transmitting periodic current through t e rails in parallel tooperate the means.

16. An electric tra c-controlling system comprising, in combination withcontinuously conductive track rails and cross-bonds of negligibleimpedance, a train or car provided with electric train or carcontrolling means responsive to the diflerence in potential of twowheels of the train or car, one in ad-.

Vance of the other, and means for transmitting a current through therails to operate the train-controlling means, said currenttransmittingmeans being connected with the rails at two cross-bonds so that theintervening portions of the two rails constitute, with the bonds, pathsof equal impedance for the current.

17. An electric traffic-controlling system comprising a contactconductor extending along a given section of the railway, a car ortrain, contact devices carried thereby and arranged to engage thecontact conductor at diiterent points, traffic-controlling apparatus onthe car or train connected With the contact devices and responsive topotential difference between them, means for transmitting a currentthrough the contact conductor, and means for controlling said current bythe traflic-governing conditions of the track in advance of the givensection of the track.

In testimony whereof I have aflixed my signature in presence of twowitnesses.

ALBERT v. T. DAY.

Witnesses HENRY D. WILLIAMS, VICTOR D. Bons'r.

